To economically obtain a steroid useful as a medicine or the like by incubating a sterol compound in the presence of protein(s) produced by a specific process under such conditions as to enable a steroid to be oxidized and the resulting oxidation product to be accumulated in the culture fluid.
This steroid is obtained by incubating a sterol compound in the presence of protein(s) under such conditions as to enable a steroid to be oxidized and the resulting oxidation product to be accumulated in the culture fluid, followed by recovering the oxidation product. The above reaction is an in vitro selective biochemical oxidation, and the above-mentioned protein(s) is produced by the following procedure: a bovine adrenocortical cDNA library is screened with a probe consisting of a partial sequence of bovine cytochrome P450 steroid 21-hydroxylase (P450C21) gene, the P450C21 gene thus obtained is integrated into a vector and expressed in host cells. By using the above protein(s) in the aforementioned process, hydrocortisone or the like useful as a medicine can be economically obtained by several stage oxidation of a sterol compound.
SELTEN GERARDUS CORNELIS MARIA
SMAAL ERIC BASTIAAN
